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In vitro cultured 3D models of CRC have been demonstrated to hold considerable worth in drug discovery, drug resistance analysis, and in studying cell-cell and cell-matrix interactions that occur in the tumor microenvironment. The 3D models resemble the in vivo physiological microenvironment by replicating the cell type composition and tissue architecture. Molecularly imprinted polymers (MIPs) have been investigated for use instead of antibodies against small non-immunogenic structures, such as sialic acid (SA). Glyco-conjugates including SA are present on all cells, and often deregulated on cancer cells. Here, we present a novel approach for targeting and detecting colorectal cancer cells (CRC) by using in vitro cultured HT29 3D spheroids co-cultured in vitro with either fluorescent MIPs targeting SA, SA-MIPs, or the two lectins targeting SA, MAL I, and SNA. Both formaldehyde-fixed and viable HT29 3D spheroids with or without SA-MIPs were imaged in 3D by confocal microscopy. The results revealed a preserved cell morphology and viability of the HT29 3D spheroids co-cultured in vitro with SA-MIPs. However, the lectins MAL I and SNA targeting the a-2,3 or a-2,6 SA glycosidic linkages, respectively, affected the cell viability when co-cultured with the viable HT29 3D spheroids, and no living cells could be detected. Here, we have shown that the SA-MIPs could be used as a safe and low-cost diagnostic tool for targeting and detecting cancer cells in a physiologically relevant 3D cancer model in vitro.

PIP5K1 alpha has emerged as a promising drug target for the treatment of castration-resistant prostate cancer (CRPC), as it acts upstream of the PI3K/AKT signaling pathway to promote prostate cancer (PCa) growth, survival and invasion. However, little is known of the molecular actions of PIP5K1 alpha in this process. Here, we show that siRNA-mediated knockdown of PIP5K1 alpha and blockade of PIP5K1 alpha action using its small molecule inhibitor ISA-2011B suppress growth and invasion of CRPC cells. We demonstrate that targeted deletion of the N-terminal domain of PIP5K1 alpha in CRPC cells results in reduced growth and migratory ability of cancer cells. Further, the xenograft tumors lacking the N-terminal domain of PIP5K1 alpha exhibited reduced tumor growth and aggressiveness in xenograft mice as compared to that of controls. The N-terminal domain of PIP5K1 alpha is required for regulation of mRNA expression and protein stability of PIP5K1 alpha. This suggests that the expression and oncogenic activity of PIP5K1 alpha are in part dependent on its N-terminal domain. We further show that PIP5K1 alpha acts as an upstream regulator of the androgen receptor (AR) and AR target genes including CDK1 and MMP9 that are key factors promoting growth, survival and invasion of PCa cells. ISA-2011B exhibited a significant inhibitory effect on AR target genes including CDK1 and MMP9 in CRPC cells with wild-type PIP5K1 alpha and in CRPC cells lacking the N-terminal domain of PIP5K1 alpha. These results indicate that the growth of PIP5K1 alpha-dependent tumors is in part dependent on the integrity of the N-terminal sequence of this kinase. Our study identifies a novel functional mechanism involving PIP5K1 alpha, confirming that PIP5K1 alpha is an intriguing target for cancer treatment, especially for treatment of CRPC.

Purpose: Despite the high mortality of metastatic colorectal cancer (mCRC), no new biomarker tools are available for predicting treatment response. We developed gene-mutation-based algorithms as a biomarker classifier to predict treatment response with better precision than the current predictive factors. Methods: Random forest machine learning (ML) was applied to identify the candidate algorithms using the MSK Cohort (n = 471) as a training set and validated in the TCGA Cohort (n = 221). Logistic regression, progression-free survival (PFS), and univariate/multivariate Cox proportional hazard analyses were performed and the performance of the candidate algorithms was compared with the established risk parameters. Results: A novel 7-Gene Algorithm based on mutation profiles of seven KRAS-associated genes was identified. The algorithm was able to distinguish non-progressed (responder) vs. progressed (non-responder) patients with AUC of 0.97 and had predictive power for PFS with a hazard ratio (HR) of 16.9 (p < 0.001) in the MSK cohort. The predictive power of this algorithm for PFS was more pronounced in mCRC (HR = 16.9, p < 0.001, n = 388). Similarly, in the TCGA validation cohort, the algorithm had AUC of 0.98 and a significant predictive power for PFS (p < 0.001). Conclusion: The novel 7-Gene Algorithm can be further developed as a biomarker model for prediction of treatment response in mCRC patients to improve personalized therapies.Keywords: KRAS; algorithm; colorectal cancer biomarkers; colorectal cancer metastasis; colorectal cancer progression; gene mutations.

Colorectal cancer (CRC) is the second most metastatic disease with the majority of cases detected in Western countries. Metastases are formed by circulating altered phenotype tumor cells causing 20% of CRC related deaths. Metastatic cells may show higher expression of surface molecules such as CD44, and changes in morphological properties are associated with increased invasiveness and poor prognosis. In this study, we intended to mimic the environment for metastasizing cells. Here, we used digital holographic cytometry (DHC) analysis to determine cellular morphological properties of three metastatic and two non-metastatic colorectal cancer cell lines to show differences in morphology between the CRC cells and peripheral blood mononuclear cells (PBMCs). By establishing differences in cell area, cell thickness, cell volume, and cell irregularity even when the CRC cells were in minority (5% out of PBMCs), DHC does discriminate between CRC cells and the PBMCs in vitro. We also analyzed the epithelial marker EpCAM and migration marker CD44 using flow cytometry and demonstrate that the CRC cell lines and PBMC cells differ in EpCAM and CD44 expression. Here, we present DHC as a new powerful tool in discriminating cells of different sizes in suspension together with a combination of biomarkers.

Cells adhering onto surfaces sense and respond to chemical and physical surface features. The control over cell adhesion behavior influences cell migration, proliferation, and differentiation, which are important considerations in biomaterial design for cell culture, tissue engineering, and regenerative medicine. Here, we report on a supramolecular-based approach to prepare reversible self-assembled monolayers (rSAMs) with tunable lateral mobility and dynamic control over surface composition to regulate cell adhesion behavior. These layers were prepared by incubating oxoacid-terminated thiol SAMs on gold in a pH 8 HEPES buffer solution containing different mole fractions of omega-(ethylene glycol),(2-)(4)- and omega-(GRGDS)-, alpha-benzamidino bolaamphiphiles. Cell shape and morphology were influenced by the strength of the interactions between the amidine-functionalized amphiphiles and the oxoacid of the underlying SAMs. Dynamic control over surface composition, achieved by the addition of inert filler amphiphiles to the RGD-functionalized rSAMs, reversed the cell adhesion process. In summary, rSAMs featuring mobile bioactive ligands offer unique capabilities to influence and control cell adhesion behavior, suggesting a broad use in biomaterial design, tissue engineering, and regenerative medicine., Funding Agencies|Swedish Research Council [2018-04930, 757797]; Marie Sklodowska-Curie Actions [2018-03872, 658953]; European Research Council (ERC) EU Horizon 2020 [752604]

Digital holographic (DH) microscopy is a unique noninvasive method to analyze living cells. With DH microscopy, in vitro cell cultures can be imaged in 2D and pseudo-3D and measurements of size and morphology of the cells are provided. Here, a description of a novel methodology utilizing DH microscopy for the analysis of spheroids is presented. A cell culture protocol is introduced and morphological parameters of cell spheroids as measured by DH microscopy are presented. The study confirms the use of DH microscopy for the analysis of cell spheroids. In the future, organoids can be analyzed with DH microscopy, and it can also be used for drug response and cell death analyses. Method summary This method aims to optimize DH microscopy for the analysis of morphological parameters of spheroids in an easy and convenient way. Cell spheroids were cultured in culture dishes for 5 days. Then, the lid was replaced with HoloLid. After that, the spheroids were imaged and quantitative morphological information was collected and analyzed.

Glycoproteins are abundant on the cell surface of mammals, providing structural support, modulating cell membrane properties, and acting as signaling agents. Variation of glycosylation patterns has been found to indicate various disease states, including cell malignancy. Sialic acid (SA) is present as a terminating group on cell-surface glycans, and its overexpression has been linked to several types of cancer. Detection of SA on the cell surface is therefore critical for detection of cancer in its early stages. In this work, a fluorescent molecularly imprinted polymer layer targeting SA was synthesized on the surface of silica-coated polystyrene (PS) particles. Compared to previous works, a PS core supplies a lighter, lower-density support for improved suspension stability and scattering properties. Moreover, their smaller size provides a higher surface-area-to-volume ratio for binding. The incorporation of a fluorescent monomer in the MIP shell allowed for simple and rapid determination of binding specificity in polar media due to a deprotonation-reprotonation interaction mechanism between the fluorescent monomer and SA, which led to spectral changes. Upon titration of the MIP particles with SA in suspension, an increase in fluorescence emission of the particles was observed, with the MIP particles binding SA more selectively compared to the nonimprinted polymer (NIP) control particles. In cell staining experiments performed by flow cytometry, the binding behavior of the MIP particles compared favorably with that of SA-binding lectins. NIPs prepared with a "dummy" template served as a better negative control in cell binding assays due to the favorable inward orientation of template-binding functional groups in the polymer shell, which reduced nonspecific binding. The results show that fluorescent MIPs targeting SA are a promising tool for in vitro fluorescence staining of cancerous cells and for future diagnosis of cancer at early stages.

Breast cancer is the second most common cancer type worldwide and breast cancer metastasis accounts for the majority of breast cancer-related deaths. Tumour cells produce increased levels of sialic acid (SA) that terminates the monosaccharide on glycan chains of the glycosylated proteins. SA can contribute to cellular recognition, cancer invasiveness and increase the metastatic potential of cancer cells. SA-templated molecularly imprinted polymers (MIPs) have been proposed as promising reporters for specific targeting of cancer cells when deployed in nanoparticle format. The sialic acid-molecularly imprinted polymers (SA-MIPs), which use SA for the generation of binding sites through which the nanoparticles can target and stain breast cancer cells, opens new strategies for efficient diagnostic tools. This study aims at monitoring the effects of SA-MIPs on morphology and motility of the epithelial type MCF-7 and the highly metastatic MDAMB231 breast cancer cell lines, using digital holographic cytometry (DHC). DHC is a label-free technique that is used in cell morphology studies of e.g., cell volume, area and thickness as well as in motility studies. Here, we show that MCF-7 cells move slower than MDAMB231 cells. We also show that SA-MIPs have an effect on cell morphology, motility and viability of both cell lines. In conclusion, by using DH microscopy, we could detect SA-MIPs impact on different breast cancer cells regarding morphology and motility.

Cancer cells often have an increased amount of glycans, such as sialic acid (SA), on the cell surface, which normally play an important role in cell growth, proliferation and differentiation. In this study, SA expression is determined by fluorescent nanoprobes, molecularly imprinted polymers, SA-MIPs. The nanoprobes are synthesized with an imprinting approach to produce tailor-made fluorescent core-shell particles with high affinity for cell surface SA. Inflammation and cytokine production are well known tumor promoters, modulating the cellular microenvironment, including an aberrant cell surface glycan pattern. The recombinant cytokines IL-4, IL-6, IL-8 and a cocktail of cytokines collected from stimulated T leukemia Jurkat cells were used to induce in vitro inflammation in two cell lines, and thereafter analyzed with the use of SA-MIPs and flow cytometry. One of cell lines showed a different binding pattern of SA-MIPs after treatment with recombinant cytokines and the cytokine cocktail. This study shows that SA-MIPs can be an important tool in the investigation of overexpressed glycans in the tumor microenvironment.

To understand complex biological processes, scientists must gain insight into the function of individual living cells. In contrast to the imaging of fixed cells, where a single snapshot of the cell’s life is retrieved, live-cell imaging allows investigation of the dynamic processes underlying the function and morphology of cells. Label-free imaging of living cells is advantageous since it is used without fluorescent probes and maintains an appropriate environment for cellular behavior, otherwise leading to phototoxicity and photo bleaching. Quantitative phase imaging (QPI) is an ideal method for studying live cell dynamics by providing data from noninvasive monitoring over arbitrary time scales. The effect of drugs on migration, proliferation, and apoptosis of cancer cells are emerging fields suitable for QPI analysis. In this review, we provide a current insight into QPI applied to cancer research.

The 6%–9% risk of an untoward outcome previously established by Warburton for prenatally detected de novo balanced chromosomal rearrangements (BCRs) does not account for long-term morbidity. We performed long-term follow-up (mean 17 years) of a registry-based nationwide cohort of 41 individuals carrying a prenatally detected de novo BCR with normal first trimester screening/ultrasound scan. We observed a significantly higher frequency of neurodevelopmental and/or neuropsychiatric disorders than in a matched control group (19.5% versus 8.3%, p = 0.04), which was increased to 26.8% upon clinical follow-up. Chromosomal microarray of 32 carriers revealed no pathogenic imbalances, illustrating a low prognostic value when fetal ultrasound scan is normal. In contrast, mate-pair sequencing revealed disrupted genes (ARID1B, NPAS3, CELF4), regulatory domains of known developmental genes (ZEB2, HOXC), and complex BCRs associated with adverse outcomes. Seven unmappable autosomal-autosomal BCRs with breakpoints involving pericentromeric/heterochromatic regions may represent a low-risk group. We performed independent phenotype-aware and blinded interpretation, which accurately predicted benign outcomes (specificity = 100%) but demonstrated relatively low sensitivity for prediction of the clinical outcome in affected carriers (sensitivity = 45%–55%). This sensitivity emphasizes the challenges associated with prenatal risk prediction for long-term morbidity in the absence of phenotypic data given the still immature annotation of the morbidity genome and poorly understood long-range regulatory mechanisms. In conclusion, we upwardly revise the previous estimates of Warburton to a morbidity risk of 27% and recommend sequencing of the chromosomal breakpoints as the first-tier diagnostic test in pregnancies with a de novo BCR.

Single-cell studies using noninvasive imaging is a challenging, yet appealing way to study cellular characteristics over extended periods of time, for instance to follow cell interactions and the behavior of different cell types within the same sample. In some cases, e.g., transplantation culturing, real-time cellular monitoring, stem cell studies, in vivo studies, and embryo growth studies, it is also crucial to keep the sample intact and invasive imaging using fluorophores or dyes is not an option. Computerized methods are needed to improve throughput of image-based analysis and for use with noninvasive microscopy such methods are poorly developed. By combining a set of well-documented image analysis and classification tools with noninvasive microscopy, we demonstrate the ability for long-term image-based analysis of morphological changes in single cells as induced by a toxin, and show how these changes can be used to indicate changes in biological function. In this study, adherent cell cultures of DU-145 treated with low-concentration (LC) etoposide were imaged during 3 days. Single cells were identified by image segmentation and subsequently classified on image features, extracted for each cell. In parallel with image analysis, an MTS assay was performed to allow comparison between metabolic activity and morphological changes after long-term low-level drug response. Results show a decrease in proliferation rate for LC etoposide, accompanied by changes in cell morphology, primarily leading to an increase in cell area and textural changes. It is shown that changes detected by image analysis are already visible on day 1 for [Formula: see text] etoposide, whereas effects on MTS and viability are detected only on day 3 for [Formula: see text] etoposide concentration, leading to the conclusion that the morphological changes observed occur before and at lower concentrations than a reduction in cell metabolic activity or viability. Three classifiers are compared and we

Sialic acid (SA) is normally expressed on the cell membranes and is located at the terminal position of the sugar chains. SA plays an important role for regulation of the innate immunity, function as markers of the cells and can be recognized by a variety of receptors. Interestingly, the level of SA expression is increased on metastatic cancer cells. The availability of specific antibodies against SA is limited and, therefore, biomarker tools for detection of SA are lacking. We have recently presented a novel method for specific fluorescence labeling of SA molecular imprinted polymers (MIP). Here, we have performed an extended screening of SA expression by using SA-MIP and included four different chronic lymphocytic leukemia (CLL) cell lines, conveniently analyzed by flow cytometry and fluorescence microscopy. SA expression was detected in four cell lines at different levels, and the SA expression were verified with lectin-FITC. These results show that SA-MIP can be used as a plastic antibody for detection of SA using both flow cytometry and fluorescence microscopy. We suggest that SA-MIP can be used for screening of different tumor cells of various stages, including CLL cells., Funding agencies: Malmö University; Cancer Foundation at Malmo University Hospital; Swedish Knowledge Foundation

We are using the label-free technique of holographic microscopy to analyze cellular parameters including cell number, confluence, cellular volume and area directly in the cell culture environment. We show that death-induced cells can be distinguished from untreated counterparts by the use of holographic microscopy, and we demonstrate its capability for cell death assessment. Morphological analysis of two representative cell lines (L929 and DU145) was performed in the culture flasks without any prior cell detachment. The two cell lines were treated with the anti-tumour agent etoposide for one to three days. Measurements by holographic microscopy showed significant differences in average cell number, confluence, volume and area when comparing etoposide-treated with untreated cells. The cell volume of the treated cell lines was initially increased at early time-points. By time, cells decreased in volume, especially when treated with high doses of etoposide. In conclusion, we have shown that holographic microscopy allows label-free and completely non-invasive morphological measurements of cell growth, viability and death. Future applications could include real-time monitoring of these holographic microscopy parameters in cells in response to clinically relevant compounds.

Background: We introduce the combination of digital holographic microscopy (DHM) and antibody microarrays as a powerful tool to measure morphological changes in specifically antibody-captured cells. The aim of the study was to develop DHM for analysis of cell death of etoposide-treated suspension cells. Result/Methodology: We demonstrate that the cell number, mean area, thickness, and volume were non-invasively measured by using DHM. The cell number was stable over time, but the two cell lines showed changes of cell area and cell irregularity after treatment. The cell volume in etoposide-treated cells was decreased, whereas untreated cells showed stable volume. Conclusions: Our results provide proof of concept for using DHM combined with antibody-based microarray technology for detecting morphological changes in captured cells.